Questions tagged [weather]
Weather means the atmospheric conditions, including wind, temperature and precipitation, in a specific area at a specific time.
294
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1answer
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Does a METAR report variable wind direction in a clockwise direction?
Does the convention for reporting variable wind direction always use a clockwise (nautical) sense?
For example, if the wind varies between 340 degrees and 10 degrees, assuming a clockwise sense the ...
2
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1answer
63 views
Is an area of localized reduced visibility considered to be a cloud?
If there an area containing visible moisture in an otherwise clear sky and that area of visible moisture is transparent is it considered a "thin cloud" or simply a "localized area of reduced ...
2
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1answer
82 views
What is an approved weather source for flying an instrument approach into an airport with no working ATIS?
What can you use as viable weather information landing at an airport with ATIS inoperative due to the tower being closed after hours? Let's assume the approach secondary weather source is also ...
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2answers
2k views
Who makes the call to start in terrible weather conditions?
I once headed to the airport during a huge thunderstorm with winds above 55 knots and massive rain and some small hail. At the airport, I saw that most flights were delayed or even canceled. To my ...
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2answers
273 views
Are helicopters impacted by fog more than airplanes?
With the crash of Kobe Bryant's helicopter, it seems a lot of focus has been placed on the helicopter flying low in fog (under "special VFR"). However, I've seen several suggestions that the ...
4
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0answers
168 views
How far can the sound of a sonic boom travel? [closed]
Are there conditions or distances from the plane to cloud to the observer in which a sonic boom from a plane is muted?
0
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2answers
93 views
Why and how do atmospheric properties sometimes vary from the ISA? [closed]
I'm curious as to why sometimes atmospheric properties don't match the ISA's. One reason I am considering is due to calibration discrepancies. By atmospheric properties I mean temperature, Density, ...
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5answers
7k views
Why did my LGA-ORD flight make an S-shaped turn round the time it was passing a storm?
On a recent United UA1709 flight into Chicago (hit by a heavy storm at the time), I felt a noticeable descent, combined with two wide banks around 1 hour before landing. Looking at the flight path, I ...
10
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1answer
1k views
How do pilots avoid thunderstorms at night over the pacific en route to Australia where there is no radar? And what if a large front develops?
While there is some limited radar on board for pilots, we hear that there is no radar over the ocean which is why flight locations are estimated. As the distance between the United States and ...
4
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1answer
179 views
What to do if trapped on top VFR?
In the event that, despite his best efforts, a VFR-only pilot has gotten trapped on top of a solid cloud layer, what is(are) the safest course(s) of action?
For example, consider a long cross-country ...
2
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1answer
97 views
How to avoid getting trapped on top VFR?
This question addresses whether it is legal to fly VFR over-the-top.
One of the comments mentioned the difference between safety and legality, i.e. doing so may not be safe even if it is legal (in ...
2
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1answer
933 views
What fomula use for calculating pressure altitude?
I'm having some trouble making my calculations of pressure altitude match those in apps and text books.
I'm using the formula from Wikipedia:
(29.92 - altimeter setting) * 1000 + airport elevation ...
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0answers
32 views
Where can I find NWS Surface Analysis charts?
It seems that a lot of documentation for getting the 'big picture' for aviation weather refers to 'Surface Analysis Charts'. For example AC 00-45H 4.1 talks about NWS Surface Analysis charts. However ...
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1answer
224 views
What is the difference between ACARS and ADS-B?
What is the difference between ACARS and ADS-B?
For weather information in-flight or pre-flight which one is used?
7
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1answer
1k views
Does the coriolis force have an effect on the direction in which an aircraft travels?
Suppose an aircraft is flying from Kenya (which lies on the equator) to UK (which lies in the northern hemisphere). Does the Coriolis force veer the aircraft to the right? Do pilots have to correct ...
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1answer
238 views
Can you continue an ILS approach when weather falls below minimum?
If, after passing the final approach fix, weather deteriorates so that the reported values are now below required minima, is it allowed to continue the approach?
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1answer
113 views
What is the reasoning behind this question about the correct altitude to avoid clear icing?
This question has been killing me for a while and it's an original PPL question:
You are approaching to an airmass with a temperature of 6 C at
10000ft. Which altitude should you be in order to ...
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vote
1answer
88 views
Why jet stream is stronger in winter?
I notice in a website taling about jetstream
https://www.weather.gov/jetstream/jet
It says:
The winds blow from west to east in jet streams but the flow often shifts
to the north and south. ...
0
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4answers
107 views
Can airflow reverse over the flight surfaces of a uav in high wind conditions
Can airflow reverse over the wing of a uav in high tail winds and low forward airspeed i.e 25knt fwd airspeed in a 35 knt tailwind? What would be the overall effect on the elevator and rudder? I ...
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2answers
380 views
Approach when weather condition is below minimum
If airport weather condition is below minimum, but pilot report that flight weather condition is above minimum, Does controller can issue approach clearance to pilot?
If weather condition get worse ...
6
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3answers
157 views
NEXRAD—why is it 2D?
If you paid attention to NEXRAD training, you know that the colors of pixels show the maximum activity at any altitude in that air column. (It’s a “composite” view.)
NEXRAD itself samples in three ...
22
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3answers
6k views
How did pilots avoid thunderstorms and related weather before “reliable” airborne weather radar was introduced on airliners?
How did airline and or mail pilots avoid hazardous weather especially at night before airborne weather radar systems were in use?
3
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1answer
178 views
Does an uncovered naval aircraft suffer any weathering affects?
This question is for WW2-era naval aircraft.
I noticed that some cruisers and battleships carried a couple seaplanes, launched by catapult and recovered with cranes.
Obviously these are unprotected ...
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2answers
1k views
What does NSC mean in a METAR?
Here's a METAR:
SCEL 090000Z 15005KT 5000 HZ NSC 10/08 Q1020 NOSIG
What does NSC mean?
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3answers
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When do flights get cancelled due to fog?
When flights get cancelled due to fog, what triggers the cancellation? Fog is too thick, too wide-spread, blocks the view of tall buildings or other landmarks? Or is the problem the type of air ...
5
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1answer
119 views
What kind of input is used by NASA's TASAR?
I've found the Aviation SE to be a really interesting read so far, I'm excited to be here! I'm fairly new, but I'm also old!
What are the inputs for TASAR to crunch flight path optimization? Is it ...
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1answer
72 views
What the weather condition can affect for flight? [closed]
What is the most disturbing weather conditions for flight?
On another word: what more dangerous for takeoff/landing: wind, precipitation or something else?
0
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3answers
137 views
What does the future of the weather radars look like?
Planes had weather radars for a long time (Dassault Falcon and Learjet35A) which was useful since you either had to ask ATC, listen the ATIS frequency or ask the flight advisory before flight planning ...
6
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4answers
743 views
What is an “all-weather” aircraft?
I've read a few times that such-and-such a plane is an "all-weather" aircraft, for example:
The McDonnell Douglas F/A-18 Hornet is a twin-engine, supersonic, all-weather, carrier-capable, multirole ...
2
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1answer
553 views
What are the duration of TAFs?
TAFs (terminal aerodrome forecast) have different durations. Some forecasts 30 hours into the future while others forecasts only 24 hours.
But what is the shortest and longest TAFs? and how often are ...
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2answers
454 views
What is the relation between clouds and radar effectiveness?
Recently, India's prime minister Narendra Modi commented on how cloudy weather can help a fighter jet escape from radar. Is there any technical reasoning to back these comments?
Here is the quote ...
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1answer
472 views
For an airport to be designated as an IFR alternate, does it have to have a TAF?
For an airport to be designated as an IFR alternate, does it have to have a terminal aerodrome forecast at the alternate airport to confirm that the forecast 600-2 and 800-2 will be in place at the ...
4
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1answer
246 views
Why is a small amount of smooth ice over the top of the wing more dangerous than an accumulation on the leading edge?
According to a Gleim study guide,
"Generally speaking, smooth ice on top of the wing is more dangerous than heavy accumulated icing on the leading edge."
Is this true? If this is true, why?
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3answers
796 views
Are there more accidents in winter months, and if so, why?
I was watching The Flight Channel videos and have noticed that the accidents seem to happen more often in winter months (for the Northern Hemisphere). Are there some statistics to back this claim?
It ...
2
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1answer
704 views
What is the meaning of R88/70D in this METAR from Ashgabat International airport?
The following METAR is from Ashgabat airport (UTAA)
UTAA 071300Z 13006KT 9999 FEW050CB BKN050 BKN100 15/06 Q1013 R88/70D
NOSIG
What does R88/70D mean, I couldn't find any references?
3
votes
1answer
164 views
Is navigation around thunderheads done at the pilot's discretion?
It's my understanding that if a pilot is flying over an ocean or otherwise uncontrolled airspace and they encounter a cumulonimbus, they navigate around it at their discretion.
How does this happen ...
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3answers
1k views
What is the purpose of including sea level pressure and temperature in a METAR?
In a METAR such as this one:
KGOK 161553Z AUTO 18011KT 4SM BR OVC007 07/05 A3011 RMK AO2 SLP201
T00670050
Translated to:
Jan 16, 1553Z, Automated. Mist, Wind from 180° at 11 knots, 4 statute
...
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3answers
127 views
How is the effect of wind on arrival time handled?
If a commercial plane encounters strong tailwinds, would the pilots set the autopilot for a fixed arrival time (if that is possible), or would it be ok to arrive way ahead of schedule?
I imagine ...
3
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1answer
131 views
When is a high pressure system associated with IFR/MVFR conditions?
So I've read that typically high pressure systems bring good weather and clear skies. However, for the current high pressure system we're experiencing in central USA, we're having quite a bit of IFR/...
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1answer
58 views
Can a SIGMET last less than initially forecasted?
Lets say I have a SIGMET that says VALID 310800/311200.
Is it possible that by 1100 the SIGMET would not be active anymore or it will always be valid until the published end time?
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3answers
440 views
Did AF447 cross dangerous weather?
question
Did the Air France 447 pilots endanger the passengers by not diverting around but flying straight through the weather system encountered and pictured below ? Or was this a defendable, ...
2
votes
1answer
433 views
When do pilots facing bad weather turn back (U-turn)?
Passenger aircraft are not supposed to cross red areas on the weather radar. But what if the weather system is too large to circumnavigate and red areas inside the system are too large/prevalent to ...
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4answers
214 views
Are winds that are not from the prevailing wind direction more often gusty, and why?
It seems to me that, looking at the ground weather forecasts (as opposed to, say, low level forecasts), it's far more common for the wind to be predicted to be significantly gusty when it is blowing ...
3
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3answers
732 views
How do pilots decide whether to circumnavigate bad weather?
How does an airline pilot decide in the air whether to circumnavigate or fly through bad weather visibly looming ahead and/or displayed on the weather radar ?
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0answers
65 views
What is the specific FAA regulation with regards to a pilot dropping jumpers into a solid cloud base? [duplicate]
What is the FAA regulation with regards to a pilot dropping jumpers into a solid cloud base? I saw some parachute jumpers come through a solid cloud layer with a base at around 1300 AGL. They landed ...
1
vote
1answer
284 views
Do any civilian aircraft use AESA or PESA for weather radar?
Are there any weather radars in civilian aircraft that uses active or passive array techniques? I know that the most of the radar used in the civilian aircraft use doppler effect and latest military ...
3
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1answer
322 views
What if the tower Is obstructed by clouds?
I know towers use radar to watch aircraft, obviously. But what about ground controllers? What if their view is obstructed by a low cloud level/fog?
Is there such a thing as ground-based traffic ...
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2answers
67 views
Remote access to Area Forecast Discussion
Is it possible to access Area Forecast Discussion via SMS? I fly to remote areas frequently (Wilderness), and after several days, it is almost impossible to get a good weather forecast, (one you're ...
3
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0answers
141 views
Diversions because of fog: What are the reasons?
It's fog season again around my local airport MUC (EDDM), and I have noticed a number of diversions recently. Some planes were holding a bit before attempting to land, performed a go around and then ...
2
votes
1answer
118 views
With wind, what will a perfectly circular flight path relative to the surrounding air look like from the ground? [duplicate]
Let's suppose that an airplane flying at a uniform airspeed follows a perfect, level, closed circular trajectory with respect to the mass of air. Now, seen from the ground, and in the presence of a ...
